Many methods have been proposed for user identification through biometrics. One of the more promising techniques is that of iris recognition. Various camera systems exist to capture images of the iris. One of the challenges of biometric camera systems is operating in ambient light, e.g. being able to capture images of the iris in full sunlight, with sufficient discrimination at an imaging sensor to determine the identity of the person. Bright ambient light, particularly in the near infrared (NIR) region, can saturate the image sensor, and can also create shadows that make it difficult to capture a consistent iris image.